From: Eric Botcazou <ebotca...@adacore.com>
Assignment statements marked with the No_Ctrl_Actions or No_Finalize_Actions
flag are initialization statements and, therefore, no temporaries are needed
to hold the value of the right-hand side for them.
gcc/ada/ChangeLog:
* gcc-interface/trans.cc (Call_to_gnu): Always use the return slot
optimization if the parent node is an initialization statement.
(gnat_to_gnu) <N_Assignment_Statement>: Build an INIT_EXPR instead
of a MODIFY_EXPR if this is an initialization statement.
Tested on x86_64-pc-linux-gnu, committed on master.
---
gcc/ada/gcc-interface/trans.cc | 15 ++++++++++++++-
1 file changed, 14 insertions(+), 1 deletion(-)
diff --git a/gcc/ada/gcc-interface/trans.cc b/gcc/ada/gcc-interface/trans.cc
index cda73d509e8..b65a846ee66 100644
--- a/gcc/ada/gcc-interface/trans.cc
+++ b/gcc/ada/gcc-interface/trans.cc
@@ -5517,10 +5517,17 @@ Call_to_gnu (Node_Id gnat_node, tree
*gnu_result_type_p, tree gnu_target,
gigi_checking_assert (!Do_Range_Check (gnat_node));
+ /* If the parent is an initialization statement, we can use the
+ return slot optimization. */
+ if (Nkind (gnat_parent) == N_Assignment_Statement
+ && (No_Ctrl_Actions (gnat_parent)
+ || No_Finalize_Actions (gnat_parent)))
+ op_code = INIT_EXPR;
+
/* ??? If the return type has variable size, then force the return
slot optimization as we would not be able to create a temporary.
That's what has been done historically. */
- if (return_type_with_variable_size_p (gnu_result_type))
+ else if (return_type_with_variable_size_p (gnu_result_type))
op_code = INIT_EXPR;
/* If this is a call to a pure function returning an array of scalar
@@ -7811,6 +7818,12 @@ gnat_to_gnu (Node_Id gnat_node)
= build_unary_op (ADDR_EXPR, TREE_TYPE (arg), gnu_lhs);
}
+ /* If the statement is an initialization, build one too. */
+ else if (No_Ctrl_Actions (gnat_node)
+ || No_Finalize_Actions (gnat_node))
+ gnu_result
+ = build_binary_op (INIT_EXPR, NULL_TREE, gnu_lhs, gnu_rhs);
+
/* Otherwise build a regular assignment. */
else
gnu_result
--
2.43.0
